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of mining on the hydrologic balance. The No. 1 and No. 3 mine drainages aze combined, and dischazge at CPDS dischazge point 001, within the mine site. In accordance with the CDPS pemut, this dischazge is monitored for flow rate, total suspended solids, pH, oil and grease, total recoverable iron, potentially dissolved iron, potentially dissolved cadmium, total dissolved solids, and chronic whole effluent toxicity. Dischazge at point 005, the outfall of the Refuse Area Pond, is monitored for flow rate, pH, oil and grease, settleable solids, and total dissolved solids. See the CPDS permit for frequency of sampling. In addition, the renewal of the current CPDS pemut included aone-time sample for analysis of potentially dissolved copper, potentially dissolved lead, total mercury, potentially dissolved selenium, and potentially dissolved silver. This prerequisite sample was taken on July 17, 2001. The quality of water dischazged at Outfa11001 has been consistently in compliance with CDPS requirements. There has been no recorded incidence of a dischazge at Outfa11005. h1 addition, upstream and downstream monitoring of surface water is accomplished in a manner approved by the Division [Rule 2.05.6(3)(b)(iv)]. North Thompson Creek sites aze sampled for conductivity, TDS, pH, Ca, Fe, Mn, SOa, TSS, HCOs, Cl, Mg, Na and Zn. The sampling frequency is biannual. There is no current monitoring of the Middle Thompson Creek (southern extent of underground mining) or of the Roaring Fork River (the loadout site). 2. Ground Water Monitoring Ground water monitoring is accomplished at the two piezometers D-lA and D-2A, and includes the parameters of water level, temperature, pH, and conductivity. Piezometer D- lA is located in North Thompson Creek alluvium in proximity of the foot of the mine waste pile. Piezometer D-2A is located in the same alluvium, but upstream (North Thompson Creek) a short distance from the mine waste pile azea. There is no groundwater monitoring in the Middle Thompson Creek drainage or at the loadout site (Roazing Fork River). Ground water points of compliance (wells) are required for an operation that has the potential to negatively impact the quality of ground water.The bedrock ground-water at the North Thompson Creek Mine is in formations whose permeability is too low for mine leachate to significantly infiltrate into the rock; therefore, there is no potential for negative impact, and consequently a compliance point is not required for the bedrock formations. The absence of potential for negatively impacting bedrock ground water indicates the mine is in compliance with the Basic Standazds for Ground Water in bedrock formations. Leachate seeping from the mine's refuse pile has the potential for negatively impacting the alluvium downgradient (southeast) from the refuse pile. The mine monitors North 15